Grinding apparatus



June 20, 1933. I w. N. APPLETON 1,915,144

GRINDING APPARATUS Filed Jan. 2, 1929 IIIHIIIIII-IIIN INVENTOR Patented June 29, 1933 outrun STATES PATENT m s WALLACE N. APPLETON, OF GRAFTON, PENNSYLVANIA, ASSIGNOR, BY ASSIGN- MENTS, T THE MCKAY COMPANY, CF PITTSBURGH, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA GRINDING APEAEATU S Application filed January 2,1929. Serial No. 3539,7594.

My invention relates to improvements in grinding and polishing apparatus, and more particularly to apparatus for grindlng or surfacing metal or the like by means of an abrasive, and is hereinafter described as used for grinding metal bars, such as impact receiving bars of automobile fender guards, but it will be understood that the invention is susceptible of use in various other ways.

One object of my invention is to provide improved means for'maintaining the work in operative relation with a grinding wheel and to thereafter automatically discharge the work.

Another object of my invent-ion is to provide means for controlling the weight of the grinding wheel on the work, in order that the grinding action may be the same on varying surfaces of the work.

Still another object of my invention is to provide a simplified and improved grinding device for surfacing bumperettes, or fender guard bars of peculiar or varying shapes.

One form which my invention may ta e is shown in the accompanying drawing, wherein Figure 1 is a side elevational view of the device, showing some of the parts in section. Fig. 2 is an end elevational view of the device, and Fig. 3 is a side view of the shaper plate.

A framework or pedestal 1 is provided for supporting a head member 2 that has dovetail connection with the pedestal and which is slidably adjustable thereon by means of a handwheel 3, in any suitable manner wellknown in the art. A beam 4 is pivotally mounted on the head member 2 and is bifurcated to form forwardly-extending arms 5 and 6 which terminate in hearings to support a shaft 7. A pulley 8 is mounted on the shaft 7, between the arms 5 and 6, and is driven by a belt 9 from suitable source of power. The belt 9 extends substantially parallel to the beam'4, so that the beam may oscillate slightly without excessive stretching of the belt or seriously interfering with the driving function thereof. A grinding wheel 10 is keyed, or otherwise, secured to one end of the shaft 7, and a guide wheel 11 59 is loosely mounted on the other end.

The portion of the beam 1 which carries the grinding wheel is heavier than the portion whichis disposed at the opposite side of the pivotal mounting, and may be partially counterbalanced by means of aspring12', One end of which is. secured to the base 1 and the other end connected to an eye bolt 13. The eye'bolt13 is adjustably positioned upon the beam 4 to permit variation of spring tension thereon. I

A work carrier and grinding pressure control device, designated generally at 1 1,18 positioned beneath and in cooperative relation with the grinding and guide wheels 10 and 11. This device comprises a drive shaft 15 supported at each end in bearings of the supporting standards 16. A drive pulley 17 is suitably mounted on the shaft 15 and is driven by the belt 18 from any suitablesource of power. r

A head or hub 19, is keyed to the shaft 15 and is provided with work supporting devices 20 which are secured to the periphery of the hub. Each of the work-supporting devices 20 may be formed of flat spring steel toresiliently support the work, if desired.

Thedevices 20 are provided with suitably formed head portions 21 upon which the work is positioned.- A shaperplate 22 is securely mounted on the shaft 15in co-operative engagement with the-guide Wheel 11 which contacts with the periphery thereof.

The plate 22 is formed to conform with the varying and changing surface of the work when it is in position on the supporting device. r

, The work is represented as consisting of fender guard bars or bumperettes 23, such as are employed in automobile bumper structures used to protect the rear fenders of automobiles, the bars being shown as having an eye or lug 24; formed on their outer ends. In operating the device to grind the surface of the bars, the shafts 7 and 15 are rotated in the direction indicated by the arrows. It will be seen that with the machine in operation without work being positioned upon the supports, the Wheel 11 will freely roll on the periphery of the shaper plate 22 thus supporting the entire weight of the grinding wheel and maintaining a definite constant space between the contour of the work holder and the grinding wheel, thus permitting the work holder to freely rotate.

The grinding wheel-1O is driven at a greater speed than, and in an opposite direction, to the device 14. An operator will position a bar 23 on the head of the approaching work holder 21 with the eye 24 of the bar disposed to engage the end of the head 21 which is beveled on its lower side to securely engage the side of the eye. I

The operator will maintain the bar in this position on the work holder until the end of the bar engages the grinding wheel 10, the drag or pulling action of the wheel upon the bar maintaining it in operative position.

It is not essential that the hub or carrier 19 be driven in a direction 0 posite to the rotation of the grinding whee 10, but can have the same direction of rotation, providing the wheel 10 is driven at such speed that it will exert the required pull on the bars 23 to hold them on the carrier. 1

During the grinding operation, the shaper plate 22 causes the beam and the grinding wheel 10 to follow the particular curve or shape of the bar, suificient clearance being provided to permit a substantially uniform grinding action on the surface of the bars. I

When the bar has been carried past the grinding wheel, it will be suspended by the hook engagement of the eye with the end of the work holder, and upon further rotation of the device 14, will be delivered to a suitable receptacle. The bar is then ready for enamelling or plating, in the usual manner, if desired.

I claim as my invention 1. Grinding apparatus for bars of nonuniform curvature comprising an abrading wheel, a rotatable carrier. means for yieldably urging the wheel toward the carrier, worksupporting devices on said carrier comprising radially-extending arms having head portions of leaf spring steel extending in a' direction generally circumferentially of the carrier, and having stop portions for preventing shifting of the bars during the grinding thereof, the said head portions being unsupported at their extremities.

2. Grinding apparatus for bars of non-uniform curvature comprising a rocking frame, an abrading wheel carried thereby, a guide wheel carried by the frame, a rotatable carrier, means for yieldably urging the wheel toward the carrier,'a template rotatable with the carrier and engaged by the guide wheel, work-supporting devices on said carrier comprising radially-extending arms having head portions of leaf spring steel extending in a direction generally circumferentially of the carrier, and having stop portions for preventing'shifting of the bars during the grinding thereof, the said head portions each being unsupported at one extremity.

3. Grinding apparatus for bars of nonuniform curvature comprising a rocking frame, an abrading wheel carried thereby, a guide wheel carried by the frame, a rotatable carrier, means for yieldably urging the wheel toward the carrier, a template rotatable with the carrier and engaged by the guide wheel, work-supporting devices on said carrier comprising radially-extending arms having head portions of leaf spring steel extending in a direction generally circumferentially of the carrier, and having stop portions for preventing shifting of the bars during the grinding thereof, the said radial arms being flexible and each connected to its head portion inter mediate the ends of said portion.

In testimony whereof I, the said WALLACE N. APrLnroN, have hereunto set my hand.

WALLACE APPLETON. 

